If you want to see drivers trail each other within 0.3 of a second you need to do something on the dirty air and remove the DRS.
Exactly the dirty air is the issue. You can have crappy tyres, fuel restrictions, whatever, but what kills close racing is aero that both 1) needs undisturbed air to work properly and 2) leaves a horrid mess of vortexes behind.
But many fans are asking for faster racing. Faster racing means more speed in the corners. More speed in the corners means better aero. Better aero means... less close racing. Also other fans are asking for more freedom to the engineers. Well, ate least the aero ones with freedom are going to make the dirtiest air they can behind, get pole and dammed be the rest. And others are now asking for refueling (!), which stats in hand was the worst thing ever for overtaking.
Seems clear to me something has to change, but also that many of the popular changes are absolutely senseless.
On the other hand maybe drivers are brainwashed to with all this eco crap and lets save the tire talk. Some 17 year old rookie has showed it is actually possible to overtake with proper outbraking >> no DRS freepass and underpowered engine to get pass drivers. Sometimes I have the feeling they take this completely in consideration and are not even willing to give it a shot.
When Nico was complaining about Lewis driving to slow in China I was like, damn if you are faster in a equal car then just go for it some other rookie is showing the complete opposite.
Equal car and pretty much equal tyres is definitely not what Max had in his overtakes (unlike Nico/Lewis which all over the season had mirror cars 99% of the time). The difference between the mercs is usually under a second/lap.
Still, I am sure it could possible to hang on to the car in front 5 laps, wait for the slightest error, dive in and pass... only to lose two places later because you took 12+ laps of tire life in those 5 laps.
I can hardly believe that if there was not a big and clear downside to do so it would not be tried often, I mean, I trust a big more the racecraft of HAM/ALO/VET/RAI... that a slightly hotheaded 17 year old that has half a season on him. If they say hanging on close is no good, then is probably no good.